The Mexican army says its fight against surging opium production that feeds U.S demand is increasingly complicated by the rise of smaller gangs disputing wild, ungoverned lands planted with ever-stronger poppy strains.

The gangs have engulfed the state of Guerrero in a war to control poppy fields, turning inaccessible mountain valleys of endemic poverty and famous beach resorts into Mexico’s bloodiest spots.

From this frontline of the fight against heroin, Col. Isaac Aaron Jesus Garcia — who runs a base in one of the state’s most unruly cities, Ciudad Altamirano — sees a direct link between a record U.S. heroin epidemic that killed nearly 13,000 people in 2015 and violence on his patch.

Heroin use in the United States has risen fivefold in the past decade, and addiction has more than tripled, with the biggest jumps among whites and men with low incomes. (Reuters)

A soldier stands guard beside poppy plants before a poppy field is destroyed during a military operation in the municipality of Coyuca de Catalan, Mexico, April 18, 2017. (Photo: Henry Romero/Reuters)

Soldier standing next to poppy plants

Col. Isaac Aaron Jesus Garcia, left, stands next to poppy plants before a poppy field is destroyed during a military operation in the municipality of Coyuca de Catalan, Mexico, April 18, 2017. (Photo: Henry Romero/Reuters)

Soldiers in vehicle

Soldiers sit atop a military vehicle as they arrive for an operation to destroy a poppy field in the municipality of Coyuca de Catalan, Mexico, April 18, 2017. (Photo: Henry Romero/Reuters)

Soldier using machete

A soldier uses his machete to chop poppy plants during a military operation in the municipality of Coyuca de Catatlan in Mexico, Mexico, April 18, 2017. (Photo: Henry Romero/Reuters)

Poppy plants in field

Poppy plants are shown in a field before they are destroyed during a military operation in the municipality of Coyuca de Catalan, Mexico, April 18, 2017. (Photo: Henry Romero/Reuters)

Soldiers taking position

Soldiers take position to guard an area where poppy plants are being destroyed during a military operation in the municipality of Coyuca de Catalan, Mexico, April 18, 2017. (Photo: Henry Romero/Reuters)

Soldier holding lanced Poppy

A soldier holds a lanced poppy bulb to show how to extract the sap, which is used to make opium, during a military operation to destroy a poppy field in the municipality of Coyuca de Catalan, Mexico, April 18, 2017. (Photo: Henry Romero/Reuters)

Lanced poppy bulbs

Lanced poppy bulbs are shown in a field during a military operation in the municipality of Coyuca de Catalan, Mexico, April 18, 2017. (Photo: Henry Romero/Reuters)

Soldier holding poppy plants

A soldier holds poppy plants after a poppy field was destroyed during a military operation in the municipality of Coyuca de Catalan in Mexico, April 18, 2017. (Photo: Henry Romero/Reuters)

Soldiers standing guard

Soldiers stand guard during a military operation in the municipality of Coyuca de Catalan, Mexico, April 18, 2017. (Photo: Henry Romero/Reuters)

Soldier in middle of poppy field

A soldier is shown in a poppy field before a military operation in the municipality of Coyuca de Catalan, Mexico, April 18, 2017. (Photo: Henry Romero/Reuters)

Soldiers walking near poppy fields

Soldier walk in an area where poppy plants are being destroyed during a military operation in the municipality of Coyuca de Catalan, Mexico, April 18, 2017. (Photo: Henry Romero/Reuters)

Soldier using knife to lance poppies

A soldier uses a knife to lance a poppy bulb during a military operation to destroy a poppy field in the municipality of Coyuca de Catalan, Mexico, April 18, 2017. (Photo: Henry Romero/Reuters)

Soldier showing inside of split poppy

A soldier holds a split poppy bulb during a military operation to destroy a poppy field in the municipality of Coyuca de Catalan, Mexico, April 18, 2017. (Photo: Henry Romero/Reuters)

Poppy plants being burned

Soldiers burn poppy plants during a military operation in the municipality of Coyuca de Catatlan in Mexico, April 18, 2017. (Photo: Henry Romero/Reuters)

Soldier using machete

Soldiers destroy poppy plants during a military operation in the municipality of Coyuca de Catatlan in Mexico, April 18, 2017. (Photo: Henry Romero/Reuters)